Could you describe the format of the graphics a little bit
better? If they are fairly rectangular, creating the images
as gifs directly in perl should not be too hard. Making a png
is a bit more complicated, and you'll have to use libpng (in C)
For legal reasons it should be png (maybe with a little switch to get
gifs if people decide to...
And yes, they are fairly rectangle: it's just a little plot
of a timeseries using some additional data for errorbars